The present invention relates to an active magnesium chloride based carrier containing an alcohol and olefin polymerization catalyst components made from the same, and more particularly, to an active magnesium chloride based carrier used for olefin polymerization and solid catalyst components for olefin polymerization made from the same.
Olefin polymerization catalysts prepared by supporting a titanium halide compound onto active anhydrous magnesium chloride have been described in a number of patent documents. For example, U.S. Pat. Nos. 4,298,718 and 4,495,338 disclose an active magnesium chloride characterized in that in its X-rays powder diffraction spectrum, the characteristic diffraction lines of the inactive anhydrous xcex1-MgCl2 all become diffused halos, the most intense diffraction line which is present in the powder diffraction spectrum of the anhydrous xcex1-MgCl2 does not appear and in its place, a halo of the halogen which is the most intense appears, and such a most intense halo of the halogen shifts to a smaller angle relative to the most intense diffraction line of the inactive halide.
It is well known that the active MgCl2 is prepared by reacting anhydrous xcex1-MgCl2 with an alcohol to form an adduct and then a titanium halide compound is supported onto such an adduct to form a solid catalyst component for olefin polymerization. For example, Chinese Patent Application Publication No. CN1047302A discloses an active magnesium halide based solid catalyst component, having an X-rays powder diffraction spectrum where a) halos appear at 2xcex8 of 35xc2x0 and 14.95xc2x0 (the characteristic diffraction lines of MgCl2) or b) the halo at 2xcex8 of 350 is substituted by a halo with the maximum intensity between 33.5xc2x0 and 352xcex8 and the diffraction line at 2xcex8 of 14.95xc2x0 is absent. Said catalyst component is obtained by partially dealcoholizing a MgCl2xe2x80xa2 alcohol adduct to an alcohol content of less than 2 mole so as to form a carrier and then reacting such a carrier with a titanium halide compound.
U.S. Pat. No. 4,421,674 discloses a process for the preparation of a supported catalyst for olefin polymerization, comprising the steps of providing a solution consisting of anhydrous MgCl2 dissolved in an alcohol, spray drying said solution by spraying the latter into a flow of nitrogen so as to partially dealcoholize to form a carrier containing 1.5-20% by weight of alcohol and having an X-rays powder diffraction spectrum wherein the most intense diffraction line appears at 2xcex8 of 8.15xc2x0, there are also the characteristic diffraction lines at 2xcex8 of 9.65xc2x0 and 13.15xc2x0, and the characteristic diffraction lines of anhydrous crystalline xcex1-MgCl2 are absent. There is only one most intense diffraction line at 2xcex8 of 8.15xc2x0 in the power diffraction spectrum of the catalyst made from such a carrier and no other diffraction lines appear.
EP700936A discloses a process for producing a solid catalyst component for olefin polymerization, which comprises the preparation of a MgCl2xe2x80xa2 EtOH adduct, comprising the steps of: (A) preparing a MgCl2xe2x80xa2 mROH mixture where R is C1xcx9cC10 alkyl and m is 3.0xcx9c6.0; (B) spray-cooling said mixture to obtain a solid adduct which has the same composition as said mixture; (C) partially dealcoholizing said adduct to a molar ratio of alcohol/MgCl2 in the adduct of 0.4xcx9c2.8:1. The adduct (C) prepared according to this document has an X-rays powder diffraction spectrum wherein a novel peak does not occur at a diffraction angle 2xcex8=7xcx9c8xc2x0 as compared with the X-rays powder diffraction spectrum of the solid component (B), or even if it occurs, the intensity of the novel peak is 2.0 times or less the intensity of the highest peak present in the diffraction angle 2xcex8=8.5xcx9c9xc2x0 of the X-rays powder diffraction spectrum of the solid component (C). FIG. 2 of this document shows the typical X-rays powder diffraction spectrum of the adduct prepared in step (B), wherein the most intense diffraction line appears at 2xcex8 of 8.8xc2x0 and two less intense diffraction lines appear at 2xcex8 of 9.5xcx9c10xc2x0 and 13xc2x0, respectively. FIG. 3 of this document shows the typical X-rays powder diffraction spectrum of the adduct prepared in step (C), wherein the diffraction line at 2xcex8 of 7xcx9c8xc2x0 is absent, the most intense diffraction line appears at 2xcex8 of 8.8xc2x0 and two less intense diffraction lines appear at 2xcex8 of 9.5xcx9c10xc2x0 and 11xcx9c11.5xc2x0, respectively, with the lines being somewhat broadened. In addition, Japanese Patent Application Laid-open No. Hei 8-20607 similarly discloses a process for producing an active magnesium chloride carrier as mentioned above.
WO98/44009 discloses a magnesium chloridexe2x80xa2 alcohol adduct suitable for preparing catalysts for synthesizing stereoregular polyolefins. Said adduct has a formula of MgCl2xe2x80xa2 mROHxe2x80xa2nH2O, in which R is C1xcx9cC10alkyl, 2=m=4.2, 0=n, =0.7. In the X-rays powder diffraction spectrum of the adduct, three diffraction lines appear in the range of 2xcex8 between 5xc2x0 and 15xc2x0, respectively at 2xcex8 of 8.8xc2x10.2xc2x0, 9.4xc2x10.2xc2x0 and 9.8xc2x10.2xc2x0, the most intense diffraction line being the one at 2xcex8=8.8xc2x10.2xc2x0, the intensity of the other two diffraction lines being at least 0.2 times the intensity of the most intense diffraction line. Said adduct is prepared by dispersing magnesium chloride in an inert liquid, adding an alcohol in a gaseous phase at elevated temperature so as to completely melt thus-obtained adduct, emulsifying the molten adduct in an inert liquid medium and finally quenching the emulsion, thus obtaining the solid adduct having the special X-rays powder diffraction spectrum as mentioned above.
The object of the present invention is to provide a novel magnesium chloride based carrier containing an alcohol and having a special X-rays powder diffraction spectrum, which can be directly obtained by reacting an alcohol with magnesium chloride.
Another objection of the present invention is to provide a solid catalyst component made from the above carrier.